Commit Graph

337 Commits

Author SHA1 Message Date
Robert Watson
ac2456bfc3 Downgrade XXX to a Note for fgetsock() and fputsock().
MFC after:	3 days
2008-10-12 20:03:17 +00:00
Ed Schouten
bc093719ca Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

  The old TTY layer has a driver model that is not abstract enough to
  make it friendly to use. A good example is the output path, where the
  device drivers directly access the output buffers. This means that an
  in-kernel PPP implementation must always convert network buffers into
  TTY buffers.

  If a PPP implementation would be built on top of the new TTY layer
  (still needs a hooks layer, though), it would allow the PPP
  implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

  With the old TTY layer, it isn't entirely safe to destroy TTY's from
  the system. This implementation has a two-step destructing design,
  where the driver first abandons the TTY. After all threads have left
  the TTY, the TTY layer calls a routine in the driver, which can be
  used to free resources (unit numbers, etc).

  The pts(4) driver also implements this feature, which means
  posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

  One of the major improvements is the per-TTY mutex, which is expected
  to improve scalability when compared to the old Giant locking.
  Another change is the unbuffered copying to userspace, which is both
  used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from:		//depot/projects/mpsafetty/...
Approved by:		philip (ex-mentor)
Discussed:		on the lists, at BSDCan, at the DevSummit
Sponsored by:		Snow B.V., the Netherlands
dcons(4) fixed by:	kan
2008-08-20 08:31:58 +00:00
Ed Schouten
79da190c16 Remove unneeded D_NEEDGIANT from /dev/fd/{0,1,2}.
There is no reason the fdopen() routine needs Giant. It only sets
curthread->td_dupfd, based on the device unit number of the cdev.

I guess we won't get massive performance improvements here, but still, I
assume we eventually want to get rid of Giant.
2008-08-09 12:42:12 +00:00
John Baldwin
6bc1e9cd84 Rework the lifetime management of the kernel implementation of POSIX
semaphores.  Specifically, semaphores are now represented as new file
descriptor type that is set to close on exec.  This removes the need for
all of the manual process reference counting (and fork, exec, and exit
event handlers) as the normal file descriptor operations handle all of
that for us nicely.  It is also suggested as one possible implementation
in the spec and at least one other OS (OS X) uses this approach.

Some bugs that were fixed as a result include:
- References to a named semaphore whose name is removed still work after
  the sem_unlink() operation.  Prior to this patch, if a semaphore's name
  was removed, valid handles from sem_open() would get EINVAL errors from
  sem_getvalue(), sem_post(), etc.  This fixes that.
- Unnamed semaphores created with sem_init() were not cleaned up when a
  process exited or exec'd.  They were only cleaned up if the process
  did an explicit sem_destroy().  This could result in a leak of semaphore
  objects that could never be cleaned up.
- On the other hand, if another process guessed the id (kernel pointer to
  'struct ksem' of an unnamed semaphore (created via sem_init)) and had
  write access to the semaphore based on UID/GID checks, then that other
  process could manipulate the semaphore via sem_destroy(), sem_post(),
  sem_wait(), etc.
- As part of the permission check (UID/GID), the umask of the proces
  creating the semaphore was not honored.  Thus if your umask denied group
  read/write access but the explicit mode in the sem_init() call allowed
  it, the semaphore would be readable/writable by other users in the
  same group, for example.  This includes access via the previous bug.
- If the module refused to unload because there were active semaphores,
  then it might have deregistered one or more of the semaphore system
  calls before it noticed that there was a problem.  I'm not sure if
  this actually happened as the order that modules are discovered by the
  kernel linker depends on how the actual .ko file is linked.  One can
  make the order deterministic by using a single module with a mod_event
  handler that explicitly registers syscalls (and deregisters during
  unload after any checks).  This also fixes a race where even if the
  sem_module unloaded first it would have destroyed locks that the
  syscalls might be trying to access if they are still executing when
  they are unloaded.

  XXX: By the way, deregistering system calls doesn't do any blocking
  to drain any threads from the calls.
- Some minor fixes to errno values on error.  For example, sem_init()
  isn't documented to return ENFILE or EMFILE if we run out of semaphores
  the way that sem_open() can.  Instead, it should return ENOSPC in that
  case.

Other changes:
- Kernel semaphores now use a hash table to manage the namespace of
  named semaphores nearly in a similar fashion to the POSIX shared memory
  object file descriptors.  Kernel semaphores can now also have names
  longer than 14 chars (up to MAXPATHLEN) and can include subdirectories
  in their pathname.
- The UID/GID permission checks for access to a named semaphore are now
  done via vaccess() rather than a home-rolled set of checks.
- Now that kernel semaphores have an associated file object, the various
  MAC checks for POSIX semaphores accept both a file credential and an
  active credential.  There is also a new posixsem_check_stat() since it
  is possible to fstat() a semaphore file descriptor.
- A small set of regression tests (using the ksem API directly) is present
  in src/tools/regression/posixsem.

Reported by:	kris (1)
Tested by:	kris
Reviewed by:	rwatson (lightly)
MFC after:	1 month
2008-06-27 05:39:04 +00:00
Ed Schouten
cc8945d204 Remove redundant checks from fcntl()'s F_DUPFD.
Right now we perform some of the checks inside the fcntl()'s F_DUPFD
operation twice. We first validate the `fd' argument. When finished,
we validate the `arg' argument. These checks are also performed inside
do_dup().

The reason we need to do this, is because fcntl() should return different
errno's when the `arg' argument is out of bounds (EINVAL instead of
EBADF). To prevent the redundant locking of the PROC_LOCK and
FILEDESC_SLOCK, patch do_dup() to support the error semantics required
by fcntl().

Approved by:	philip (mentor)
2008-05-28 20:25:19 +00:00
Attilio Rao
258f4727f1 Replace direct atomic operation for the file refcount witht the
refcount interface.
It also introduces the correct usage of memory barriers, as sometimes
fdrop() and fhold() are used with shared locks, which don't use any
release barrier.
2008-05-25 14:57:43 +00:00
Konstantin Belousov
82f4d64035 Implement the per-open file data for the cdev.
The patch does not change the cdevsw KBI. Management of the data is
provided by the functions
int	devfs_set_cdevpriv(void *priv, cdevpriv_dtr_t dtr);
int	devfs_get_cdevpriv(void **datap);
void	devfs_clear_cdevpriv(void);
All of the functions are supposed to be called from the cdevsw method
contexts.

- devfs_set_cdevpriv assigns the priv as private data for the file
  descriptor which is used to initiate currently performed driver
  operation. dtr is the function that will be called when either the
  last refernce to the file goes away, the device is destroyed  or
  devfs_clear_cdevpriv is called.
- devfs_get_cdevpriv is the obvious accessor.
- devfs_clear_cdevpriv allows to clear the private data for the still
  open file.

Implementation keeps the driver-supplied pointers in the struct
cdev_privdata, that is referenced both from the struct file and struct
cdev, and cannot outlive any of the referee.

Man pages will be provided after the KPI stabilizes.

Reviewed by:	jhb
Useful suggestions from:	jeff, antoine
Debugging help and tested by:	pho
MFC after:	1 month
2008-05-21 09:31:44 +00:00
Kris Kennaway
5894445dad * Correct a mis-merge that leaked the PROC_LOCK [1]
* Return ENOENT on error instead of 0 [2]

Submitted by: rdivacky [1], kib [2]
2008-04-26 13:16:55 +00:00
Kris Kennaway
b1ba81d948 fdhold can return NULL, so add the one remaining missing check for this
condition.

Reviewed by:    attilio
MFC after:      1 week
2008-04-24 22:08:36 +00:00
Doug Rabson
dfdcada31e Add the new kernel-mode NFS Lock Manager. To use it instead of the
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.

Highlights include:

* Thread-safe kernel RPC client - many threads can use the same RPC
  client handle safely with replies being de-multiplexed at the socket
  upcall (typically driven directly by the NIC interrupt) and handed
  off to whichever thread matches the reply. For UDP sockets, many RPC
  clients can share the same socket. This allows the use of a single
  privileged UDP port number to talk to an arbitrary number of remote
  hosts.

* Single-threaded kernel RPC server. Adding support for multi-threaded
  server would be relatively straightforward and would follow
  approximately the Solaris KPI. A single thread should be sufficient
  for the NLM since it should rarely block in normal operation.

* Kernel mode NLM server supporting cancel requests and granted
  callbacks. I've tested the NLM server reasonably extensively - it
  passes both my own tests and the NFS Connectathon locking tests
  running on Solaris, Mac OS X and Ubuntu Linux.

* Userland NLM client supported. While the NLM server doesn't have
  support for the local NFS client's locking needs, it does have to
  field async replies and granted callbacks from remote NLMs that the
  local client has contacted. We relay these replies to the userland
  rpc.lockd over a local domain RPC socket.

* Robust deadlock detection for the local lock manager. In particular
  it will detect deadlocks caused by a lock request that covers more
  than one blocking request. As required by the NLM protocol, all
  deadlock detection happens synchronously - a user is guaranteed that
  if a lock request isn't rejected immediately, the lock will
  eventually be granted. The old system allowed for a 'deferred
  deadlock' condition where a blocked lock request could wake up and
  find that some other deadlock-causing lock owner had beaten them to
  the lock.

* Since both local and remote locks are managed by the same kernel
  locking code, local and remote processes can safely use file locks
  for mutual exclusion. Local processes have no fairness advantage
  compared to remote processes when contending to lock a region that
  has just been unlocked - the local lock manager enforces a strict
  first-come first-served model for both local and remote lockers.

Sponsored by:	Isilon Systems
PR:		95247 107555 115524 116679
MFC after:	2 weeks
2008-03-26 15:23:12 +00:00
Maxim Sobolev
073d8ba485 Revert previous change - it appears that the limit I was hitting was a
maxsockets limit, not maxfiles limit. The question remains why those
limits are handled differently (with error code for maxfiles but with
sleep for maxsokets), but those would be addressed in a separate commit
if necessary.

Requested by:   rwhatson, jeff
2008-03-19 09:58:25 +00:00
Robert Watson
237fdd787b In keeping with style(9)'s recommendations on macros, use a ';'
after each SYSINIT() macro invocation.  This makes a number of
lightweight C parsers much happier with the FreeBSD kernel
source, including cflow's prcc and lxr.

MFC after:	1 month
Discussed with:	imp, rink
2008-03-16 10:58:09 +00:00
Maxim Sobolev
c9370ff4d0 Properly set size of the file_zone to match kern.maxfiles parameter.
Otherwise the parameter is no-op, since zone by default limits number
of descriptors to some 12K entries. Attempt to allocate more ends up
sleeping on zonelimit.

MFC after:	2 weeks
2008-03-16 06:21:30 +00:00
Antoine Brodin
e3ad7f6626 Introduce a new F_DUP2FD command to fcntl(2), for compatibility with
Solaris and AIX.
fcntl(fd, F_DUP2FD, arg) and dup2(fd, arg) are functionnaly equivalent.
Document it.
Add some regression tests (identical to the dup2(2) regression tests).

PR:		120233
Submitted by:	Jukka Ukkonen
Approved by:	rwaston (mentor)
MFC after:	1 month
2008-03-08 22:02:21 +00:00
Dag-Erling Smørgrav
60e15db992 This patch adds a new ktrace(2) record type, KTR_STRUCT, whose payload
consists of the null-terminated name and the contents of any structure
you wish to record.  A new ktrstruct() function constructs and emits a
KTR_STRUCT record.  It is accompanied by convenience macros for struct
stat and struct sockaddr.

In kdump(1), KTR_STRUCT records are handled by a dispatcher function
that runs stringent sanity checks on its contents before handing it
over to individual decoding funtions for each type of structure.
Currently supported structures are struct stat and struct sockaddr for
the AF_INET, AF_INET6 and AF_UNIX families; support for AF_APPLETALK
and AF_IPX is present but disabled, as I am unable to test it properly.

Since 's' was already taken, the letter 't' is used by ktrace(1) to
enable KTR_STRUCT trace points, and in kdump(1) to enable their
decoding.

Derived from patches by Andrew Li <andrew2.li@citi.com>.

PR:		kern/117836
MFC after:	3 weeks
2008-02-23 01:01:49 +00:00
Simon L. B. Nielsen
1b7089994c Fix sendfile(2) write-only file permission bypass.
Security:	FreeBSD-SA-08:03.sendfile
Submitted by:	kib
2008-02-14 11:44:31 +00:00
Joe Marcus Clarke
f280594937 Add support for displaying a process' current working directory, root
directory, and jail directory within procstat.  While this functionality
is available already in fstat, encapsulating it in the kern.proc.filedesc
sysctl makes it accessible without using kvm and thus without needing
elevated permissions.

The new procstat output looks like:

  PID COMM               FD T V FLAGS    REF  OFFSET PRO NAME
  76792 tcsh              cwd v d --------   -       - -   /usr/src
  76792 tcsh             root v d --------   -       - -   /
  76792 tcsh               15 v c rw------  16    9130 -   -
  76792 tcsh               16 v c rw------  16    9130 -   -
  76792 tcsh               17 v c rw------  16    9130 -   -
  76792 tcsh               18 v c rw------  16    9130 -   -
  76792 tcsh               19 v c rw------  16    9130 -   -

I am also bumping __FreeBSD_version for this as this new feature will be
used in at least one port.

Reviewed by:	rwatson
Approved by:	rwatson
2008-02-09 05:16:26 +00:00
Robert Watson
07dd4a31b5 Export a type for POSIX SHM file descriptors via kern.proc.filedesc as
used by procstat, or SHM descriptors will show up as type unknown in
userspace.
2008-01-20 19:55:52 +00:00
Attilio Rao
22db15c06f VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
2008-01-13 14:44:15 +00:00
Attilio Rao
cb05b60a89 vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by:	Diego Sardina <siarodx at gmail dot com>,
		Andrea Di Pasquale <whyx dot it at gmail dot com>
2008-01-10 01:10:58 +00:00
John Baldwin
8e38aeff17 Add a new file descriptor type for IPC shared memory objects and use it to
implement shm_open(2) and shm_unlink(2) in the kernel:
- Each shared memory file descriptor is associated with a swap-backed vm
  object which provides the backing store.  Each descriptor starts off with
  a size of zero, but the size can be altered via ftruncate(2).  The shared
  memory file descriptors also support fstat(2).  read(2), write(2),
  ioctl(2), select(2), poll(2), and kevent(2) are not supported on shared
  memory file descriptors.
- shm_open(2) and shm_unlink(2) are now implemented as system calls that
  manage shared memory file descriptors.  The virtual namespace that maps
  pathnames to shared memory file descriptors is implemented as a hash
  table where the hash key is generated via the 32-bit Fowler/Noll/Vo hash
  of the pathname.
- As an extension, the constant 'SHM_ANON' may be specified in place of the
  path argument to shm_open(2).  In this case, an unnamed shared memory
  file descriptor will be created similar to the IPC_PRIVATE key for
  shmget(2).  Note that the shared memory object can still be shared among
  processes by sharing the file descriptor via fork(2) or sendmsg(2), but
  it is unnamed.  This effectively serves to implement the getmemfd() idea
  bandied about the lists several times over the years.
- The backing store for shared memory file descriptors are garbage
  collected when they are not referenced by any open file descriptors or
  the shm_open(2) virtual namespace.

Submitted by:	dillon, peter (previous versions)
Submitted by:	rwatson (I based this on his version)
Reviewed by:	alc (suggested converting getmemfd() to shm_open())
2008-01-08 21:58:16 +00:00
John Baldwin
e46502943a Make ftruncate a 'struct file' operation rather than a vnode operation.
This makes it possible to support ftruncate() on non-vnode file types in
the future.
- 'struct fileops' grows a 'fo_truncate' method to handle an ftruncate() on
  a given file descriptor.
- ftruncate() moves to kern/sys_generic.c and now just fetches a file
  object and invokes fo_truncate().
- The vnode-specific portions of ftruncate() move to vn_truncate() in
  vfs_vnops.c which implements fo_truncate() for vnode file types.
- Non-vnode file types return EINVAL in their fo_truncate() method.

Submitted by:	rwatson
2008-01-07 20:05:19 +00:00
Jeff Roberson
a57decdf32 - In sysctl_kern_file skip fdps with negative lastfiles. This can
happen if there are no files open.  Accounting for these can
   eventually return a negative value for olenp causing sysctl to
   crash with a bad malloc.

Reported by:	Pawel Worach <pawel.worach@gmail.com>
2008-01-03 01:26:59 +00:00
Jeff Roberson
397c19d175 Remove explicit locking of struct file.
- Introduce a finit() which is used to initailize the fields of struct file
   in such a way that the ops vector is only valid after the data, type,
   and flags are valid.
 - Protect f_flag and f_count with atomic operations.
 - Remove the global list of all files and associated accounting.
 - Rewrite the unp garbage collection such that it no longer requires
   the global list of all files and instead uses a list of all unp sockets.
 - Mark sockets in the accept queue so we don't incorrectly gc them.

Tested by:	kris, pho
2007-12-30 01:42:15 +00:00
Robert Watson
cc43c38c87 Add two new sysctls in support of the forthcoming procstat(1) to support
its -f and -v arguments:

kern.proc.filedesc - dump file descriptor information for a process, if
  debugging is permitted, including socket addresses, open flags, file
  offsets, file paths, etc.

kern.proc.vmmap - dump virtual memory mapping information for a process,
  if debugging is permitted, including layout and information on
  underlying objects, such as the type of object and path.

These provide a superset of the information historically available
through the now-deprecated procfs(4), and are intended to be exported
in an ABI-robust form.
2007-12-02 10:10:27 +00:00
Robert Watson
0bf686c125 Remove the now-unused NET_{LOCK,UNLOCK,ASSERT}_GIANT() macros, which
previously conditionally acquired Giant based on debug.mpsafenet.  As that
has now been removed, they are no longer required.  Removing them
significantly simplifies error-handling in the socket layer, eliminated
quite a bit of unwinding of locking in error cases.

While here clean up the now unneeded opt_net.h, which previously was used
for the NET_WITH_GIANT kernel option.  Clean up some related gotos for
consistency.

Reviewed by:	bz, csjp
Tested by:	kris
Approved by:	re (kensmith)
2007-08-06 14:26:03 +00:00
Jeff Roberson
f6c1ecca50 - Use explicit locking in the various fcntl case statements so that we
can acquire shared filedescriptor locks in the appropriate cases.
 - Remove Giant from calls that issue ioctls.  The ioctl path has been
   mpsafe for some time now.
 - Only acquire giant for VOP_ADVLOCK when the filesystem requires giant.
   advlock is now mpsafe.

Reviewed by:	rwatson
Approved by:	re
2007-07-03 21:26:06 +00:00
Robert Watson
7251b7863c Rather than passing SUSER_RUID into priv_check_cred() to specify when
a privilege is checked against the real uid rather than the effective
uid, instead decide which uid to use in priv_check_cred() based on the
privilege passed in.  We use the real uid for PRIV_MAXFILES,
PRIV_MAXPROC, and PRIV_PROC_LIMIT.  Remove the definition of
SUSER_RUID; there are now no flags defined for priv_check_cred().

Obtained from:	TrustedBSD Project
2007-06-16 23:41:43 +00:00
Konstantin Belousov
9e223287c0 Revert UF_OPENING workaround for CURRENT.
Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation
argument from being file descriptor index into the pointer to struct file.

Proposed and reviewed by:	jhb
Reviewed by:	daichi (unionfs)
Approved by:	re (kensmith)
2007-05-31 11:51:53 +00:00
Konstantin Belousov
5c76452f8f Mark the filedescriptor table entries with VOP_OPEN being performed for them
as UF_OPENING. Disable closing of that entries. This should fix the crashes
caused by devfs_open() (and fifo_open()) dereferencing struct file * by
index, while the filedescriptor is closed by parallel thread.

Idea by:	tegge
Reviewed by:	tegge (previous version of patch)
Tested by:	Peter Holm
Approved by:	re (kensmith)
MFC after:	3 weeks
2007-05-04 14:23:29 +00:00
John Baldwin
06e043fb20 Avoid a lot of code duplication by using kern_open() to open /dev/null
in fdcheckstd() instead of a stripped down version of kern_open()'s code.

MFC after:	1 week
Reviewed by:	cperciva
2007-04-26 18:01:19 +00:00
Robert Watson
5e3f7694b1 Replace custom file descriptor array sleep lock constructed using a mutex
and flags with an sxlock.  This leads to a significant and measurable
performance improvement as a result of access to shared locking for
frequent lookup operations, reduced general overhead, and reduced overhead
in the event of contention.  All of these are imported for threaded
applications where simultaneous access to a shared file descriptor array
occurs frequently.  Kris has reported 2x-4x transaction rate improvements
on 8-core MySQL benchmarks; smaller improvements can be expected for many
workloads as a result of reduced overhead.

- Generally eliminate the distinction between "fast" and regular
  acquisisition of the filedesc lock; the plan is that they will now all
  be fast.  Change all locking instances to either shared or exclusive
  locks.

- Correct a bug (pointed out by kib) in fdfree() where previously msleep()
  was called without the mutex held; sx_sleep() is now always called with
  the sxlock held exclusively.

- Universally hold the struct file lock over changes to struct file,
  rather than the filedesc lock or no lock.  Always update the f_ops
  field last. A further memory barrier is required here in the future
  (discussed with jhb).

- Improve locking and reference management in linux_at(), which fails to
  properly acquire vnode references before using vnode pointers.  Annotate
  improper use of vn_fullpath(), which will be replaced at a future date.

In fcntl(), we conservatively acquire an exclusive lock, even though in
some cases a shared lock may be sufficient, which should be revisited.
The dropping of the filedesc lock in fdgrowtable() is no longer required
as the sxlock can be held over the sleep operation; we should consider
removing that (pointed out by attilio).

Tested by:	kris
Discussed with:	jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
John Baldwin
3076ca6720 Just use 'fdrop()' instead of 'FILE_LOCK(); fdrop_locked()' in
dupfdopen().  While I'm at it, move the second fdrop() out from under the
filedesc lock.
2007-03-15 21:19:21 +00:00
Robert Watson
873fbcd776 Further system call comment cleanup:
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
  "syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
2007-03-05 13:10:58 +00:00
Robert Watson
0c14ff0eb5 Remove 'MPSAFE' annotations from the comments above most system calls: all
system calls now enter without Giant held, and then in some cases, acquire
Giant explicitly.

Remove a number of other MPSAFE annotations in the credential code and
tweak one or two other adjacent comments.
2007-03-04 22:36:48 +00:00
Robert Watson
780a98ad1f Catch up file descriptor printing function in DDB to the addition of kqueues
and POSIX message queues.
2007-02-15 10:55:43 +00:00
Robert Watson
442f65e958 Break file descriptor printing logic out of db_show_files() into
db_print_file(), and add a new "show file <ptr>" DDB command, which can
be used to print out file descriptors referenced in stack traces.
2007-02-15 10:50:48 +00:00
Xin LI
4f506694bb Use FOREACH_PROC_IN_SYSTEM instead of using its unrolled form. 2007-01-17 14:58:53 +00:00
John Baldwin
9ae328fc8f - Close a race between enumerating UNIX domain socket pcb structures via
sysctl and socket teardown by adding a reference count to the UNIX domain
  pcb object and fixing the sysctl that enumerates unpcbs to grab a
  reference on each unpcb while it builds the list to copy out to userland.
- Close a race between UNIX domain pcb garbage collection (unp_gc()) and
  file descriptor teardown (fdrop()) by adding a new garbage collection
  flag FWAIT.  unp_gc() sets FWAIT while it walks the message buffers
  in a UNIX domain socket looking for nested file descriptor references
  and clears the flag when it is finished.  fdrop() checks to see if the
  flag is set on a file descriptor whose refcount just dropped to 0 and
  waits for unp_gc() to clear the flag before completely destroying the
  file descriptor.

MFC after:	1 week
Reviewed by:	rwatson
Submitted by:	ups
Hopefully makes the panics go away:	mx1
2007-01-05 19:59:46 +00:00
Robert Watson
acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
John-Mark Gurney
aeab19b21f return EBADF instead of successfully attaching (and then panicing) when
an fd is dieing..

Convinced by:	jhb
PR:		103127
2006-09-24 02:29:53 +00:00
John Baldwin
b04aff773e Add a comment to explain what fdclose() does and what it's purpose is
since the subtlety eluded me when I looked at it last week.
2006-07-21 20:24:00 +00:00
John Baldwin
c1cccebe8b Add a kern_close() so that the ABIs can close a file descriptor w/o having
to populate a close_args struct and change some of the places that do.
2006-07-08 20:03:39 +00:00
Pawel Jakub Dawidek
0bd645ae0c Compress direct cr_ruid comparsion and jailed() call to suser_cred(9).
Reviewed by:	rwatson
2006-06-27 11:32:08 +00:00
Robert Watson
197b35d717 Mark fgetsock() and fputsock() as depcrecated: callers should rely on
the file descriptor reference, rather than paying additional lock
operations to acquire a socket reference from the file descriptor.
This will also help to ensure that file descriptor based socket
requests are not delivered to a socket after close.  Most consumers
have already been converted to this model.

MFC after:	3 months
2006-04-01 11:09:54 +00:00
Christian S.J. Peron
2ed4894a26 Restore fd optimization with a few minor tweaks, to quote tegge:
"fdinit() fails to initialize newfdp->fd_fd.fd_lastfile to -1.  This breaks
fdcopy() which will incorrectly set newfdp->fd_freefile to 1 if no files are
open and the last file descriptor marked as unused for fdp was 0.  This later
causes descriptor 0 to be unavailable in newfdp when the optimization is
enabled.

When the last file descriptor previously marked as used is nonzero and marked
as unused, fdunused() incorrectly sets fdp->fd_lastfile to fd - 1 due to
fd_last_used() returning (size - 1).  This hides the problem that breaks the
optimization."

This allows us to keep the optimization, while un-breaking it.

This is a RELENG_6 candidate.

PR:		kern/87208
MFC after:	1 week
Submitted by:	tegge
2006-03-20 00:13:47 +00:00
Christian S.J. Peron
30bacc08e0 Back out fd optimization introduced in revision 1.280 as it appears to be
really breaking things. Simple "close(0); dup(fd)" does not return descriptor
"0" in some cases. Further, this change also breaks some MAC interactions with
mac_execve_will_transition().  Under certain circumstances, fdcheckstd() can
be called in execve(2) causing an assertion that checks to make sure that
stdin, stdout and stderr reside at indexes 0, 1 and 2 in the process fd table
to fail, resulting in a kernel panic when INVARIANTS is on.

This should also kill the "dup(2) regression on 6.x" show stopper item on the
6.1-RELEASE TODO list.

This is a RELENG_6 candidate.

PR:		kern/87208
Silence from:	des
MFC after:	1 week
2006-03-18 23:27:21 +00:00
Wayne Salamon
a750d0b2a2 Add auditing of arguments to the close() and fstat() system calls. Much more
argument auditing yet to come, for remaining system calls in this file.

Obtained from: TrustedBSD Project
Approved by: rwatson (mentor)
2006-02-05 23:57:32 +00:00
John Baldwin
38f63f7e47 Return EBADF rather than EINVAL for FWRITE failure as per POSIX.
MFC after:	1 week
2006-01-06 16:30:30 +00:00
David Xu
b2f92ef96b Last step to make mq_notify conform to POSIX standard, If the process
has successfully attached a notification request to the message queue
via a queue descriptor, file closing should remove the attachment.
2005-11-30 05:12:03 +00:00